Evaluation of pathologists and radiologists (cone beam computed tomography) differentiating radicular cysts from granulomas

Aim To evaluate accuracy and reliability of diagnostic assessments obtained with cone beam computed tomography (CBCT) scans, comparing results with existing standard, biopsy and histopathology. Methodology CBCT scans and surgical specimens of 45 patients referred to New York University’s Department of Endodontics for periapical surgery were submitted to the Department of Endodontics of the University of Cagliari. Two maxillofacial radiologists, working independently and using the same criteria, categorized images on three groups (cyst, granuloma and other). Each surgical specimen was examined by two oral pathologists without knowledge of the clinical presentation of the patients, surgical observation of the lesions, or CBCT diagnoses. The examining oral pathologists independently determined whether tissue represented one of three categories. Inter-rater reliability between the two radiologists and the two pathologists was calculated by using the Cohen kappa coefficient. The radiologists’ and pathologists’ findings were correlated using ROC analysis. Results Agreement between the two pathologists was excellent (k = 0.84; correlations/observations: 0.914), and was significantly different from no agreement (z = 10.98, P < 0.0001). Radiologists showed a lower but good inter-rater agreement (k = 0.69; P < 0.0001). Using pathologist 1 as the standard, radiologist 1 achieved overall accuracy of 63% whereas radiologist 2 achieved an overall accuracy of 58%. Conclusions Radiologists exhibited good inter-rater agreement, but the accuracy of their diagnostic assessments compared with the histopathologic findings was significantly lower. CBCT scans have potential in endodontic diagnosis and treatment planning, but biopsy and histopathological evaluation remain the gold standard to discriminate periapical cysts from granulomas.